2DE-MALDI MS based strategy Protein(s) Enz. digestion MS Analysis DB Search DB Identities Pep. mixture Experimental Experimental mass spectrum p Trypsin 2-D gel purification Theoretical ATCGCCGTA mass spectrum LMNVCWRTYPILHK TGACTAGGI GLKINHGTRFDSK RTYPILI MFGHDSAK ACCAGTAGA CAGTAGGTA HIDSAK CGTAGCAGT ATGCAGTAC Protein Theoretical DNA sequenc database peptides database M/Z2DE-MALDI MS based strategy